Choo Sung-hoon, left, also known as Yoshihiro Akiyama, is on a four-bout losing streak since his debut UFC win in July 2009. / AP-Yonhap

By Jung Min-ho

A recent injury is posing a major challenge for UFC welterweight fighter Choo Sung-hoon, also known as Yoshihiro Akiyama, one that could even threaten his career in mixed martial arts (MMA).

Choo announced Wednesday that he is withdrawing from the UFC 149 bout against Thiago Alves, scheduled for July 21 in Calgary, Canada, , due to an anterior cruciate ligament (ACL) injury.

“I have something to tell my fans that have always supported me,” Choo said on his blog. “I was injured in training on May 5, which later turned out to be a ruptured ACL. I am planning on having an operation. With that said, I won’t be able to take part in the scheduled match in July.”

His withdrawal sees Afghanistan’s Siyar Bahadurzada, who claimed a 42-second knockout victory over Paulo Thiago in his debut match, replacing Choo. The injury will indefinitely delay Choo’s plan to bounce back from his recent loss at against Jake Shields in February.

With the news, concerns over his career in UFC have spread. Although many may miss seeing him in the ring, the 2002 Asian Games judo gold medalist is starting to do more than appearing in the octagon. He recently appeared on season two of SBS program “Law of the Jungle.” Fans were able to see a different side of the burly fighter. Choo has received positive feedback from viewers, coming across as an entertaining character. The show enjoyed a rating of more than 14 percent. Nevertheless, the fighter’s tough-guy image has waned as he has only fought in UFC five times since his debut.

Age is another concern, as Choo is now 36. He got off to a good start with a win over Alan Belcher in his first UFC fight in July, 2009 but lost the next four matches leaving him without victory in almost three years.

The judo black belt made a strong start in MMA in 2004, defeating former world heavyweight boxing champion Francois Botha in K1 with a first round submission. In K1, Choo had 10 wins,one drew, and one loss.